The decision follows a recommendation from the independent Data Safety Monitoring Board (DSMB), which oversees patient safety and evaluates ongoing trial performance. After reviewing accumulated data, the DSMB concluded that additional follow-up was unlikely to change the study’s outcome and advised that patient treatment and trial activities be discontinued.

The latest review also identified a difference in overall survival outcomes between the study arms within this patient population. According to BioNTech, this observation contributed to the DSMB’s determination that the trial should be stopped. Importantly, the board did not report any new safety-related concerns associated with autogene cevumeran.

The study had previously encountered challenges in October 2025 when it crossed a predefined futility threshold during an interim analysis. At that stage, however, the DSMB determined that the dataset was not mature enough to draw dependable conclusions regarding treatment benefit. Because the primary endpoint required longer observation and no safety issues had emerged, investigators continued the trial in accordance with the original study plan.

BNT122-01 was designed to examine whether a personalized mRNA cancer immunotherapy could lower the likelihood of disease recurrence after surgery when administered alone, without the addition of checkpoint inhibitor therapy. The comparator arm consisted of active surveillance, which currently represents standard management for these patients.

Researchers have long recognized colorectal cancer as a particularly difficult disease for immunotherapy approaches. Many colorectal tumors exhibit characteristics of an immunologically inactive, or “cold,” tumor environment, making it harder for immune-based treatments to generate effective antitumor responses. Patients with detectable ctDNA following surgery are considered at elevated risk for recurrence and metastatic progression, underscoring a continuing need for more effective treatment options.

Commenting on the outcome, BioNTech Co-Founder and Chief Medical Officer Prof. Özlem Türeci, MD, said the findings highlight the biological obstacles involved in treating tumors that are resistant to immunotherapy and shaped by immune-suppressive microenvironments. She noted that although the study did not achieve the hoped-for results for mRNA monotherapy in colorectal cancer, the data may help guide future research efforts and improve understanding of how personalized mRNA therapies can be used in oncology.

The company stated that a detailed evaluation of the trial results will now be undertaken. BioNTech plans to analyze the data for insights that may improve patient-selection strategies and support the future development of investigational mRNA-based cancer treatments. Results will be presented to the scientific and medical communities once the analyses are complete.

BioNTech emphasized that the discontinuation of BNT122-01 does not affect other ongoing programs involving autogene cevumeran. In particular, the Phase 2 IMcode003 trial, which is studying the therapy in combination with chemotherapy and checkpoint blockade in patients with resected pancreatic ductal adenocarcinoma, is continuing without changes.